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2010-05-14NFS: Reduce the stack footprint of nfs_proc_symlink()Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14NFS: Reduce the stack footprint of nfs_proc_createTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14NFS: Reduce the stack footprint of nfs_rmdirTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14NFS: Reduce stack footprint of nfs_proc_remove()Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14NFS: Reduce stack footprint of nfs3_proc_readlink()Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14NFS: Reduce the stack footprint of nfs_link()Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14NFS: Reduce stack footprint of nfs_readdir()Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14NFS: Reduce stack footprint of nfs3_proc_rename() and nfs4_proc_rename()Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14NFS: Reduce stack footprint of nfs_revalidate_inode()Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14NFSv4: Reduce stack footprint of nfs4_proc_access() and nfs3_proc_access()Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14NFSv4: Reduce the stack footprint of nfs4_remote_referral_get_sbTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14NFSv4: Reduce stack footprint of nfs4_get_root()Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14NFS: Reduce the stack footprint of nfs_follow_remote_path()Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14NFS: Reduce the stack footprint of nfs_lookupTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14NFSv4: Reduce the stack footprint of try_location()Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14NFS: Reduce the stack footprint of nfs_create_serverTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14NFS: Reduce the stack footprint of nfs_follow_mountpoint()Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14NFSv4: Eliminate nfs4_path_walk()Trond Myklebust
All we really want is the ability to retrieve the root file handle. We no longer need the ability to walk down the path, since that is now done in nfs_follow_remote_path(). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14NFS: Add helper functions for allocating filehandles and fattr structsTrond Myklebust
NFS Filehandles and struct fattr are really too large to be allocated on the stack. This patch adds in a couple of helper functions to allocate them dynamically instead. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14Merge branch 'for-linus' of git://git.infradead.org/users/eparis/notifyLinus Torvalds
* 'for-linus' of git://git.infradead.org/users/eparis/notify: inotify: don't leak user struct on inotify release inotify: race use after free/double free in inotify inode marks inotify: clean up the inotify_add_watch out path Inotify: undefined reference to `anon_inode_getfd' Manual merge to remove duplicate "select ANON_INODES" from Kconfig file
2010-05-14inotify: don't leak user struct on inotify releasePavel Emelyanov
inotify_new_group() receives a get_uid-ed user_struct and saves the reference on group->inotify_data.user. The problem is that free_uid() is never called on it. Issue seem to be introduced by 63c882a0 (inotify: reimplement inotify using fsnotify) after 2.6.30. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Eric Paris <eparis@parisplace.org> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Eric Paris <eparis@redhat.com>
2010-05-14inotify: race use after free/double free in inotify inode marksEric Paris
There is a race in the inotify add/rm watch code. A task can find and remove a mark which doesn't have all of it's references. This can result in a use after free/double free situation. Task A Task B ------------ ----------- inotify_new_watch() allocate a mark (refcnt == 1) add it to the idr inotify_rm_watch() inotify_remove_from_idr() fsnotify_put_mark() refcnt hits 0, free take reference because we are on idr [at this point it is a use after free] [time goes on] refcnt may hit 0 again, double free The fix is to take the reference BEFORE the object can be found in the idr. Signed-off-by: Eric Paris <eparis@redhat.com> Cc: <stable@kernel.org>
2010-05-14inotify: clean up the inotify_add_watch out pathEric Paris
inotify_add_watch explictly frees the unused inode mark, but it can just use the generic code. Just do that. Signed-off-by: Eric Paris <eparis@redhat.com>
2010-05-13Merge branch 'master' of /pub/scm/linux/kernel/git/torvalds/linux-2.6Steve French
Conflicts: fs/cifs/inode.c
2010-05-13Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6: cifs: guard against hardlinking directories
2010-05-13nfsd4: implement reclaim_completeJ. Bruce Fields
This is a mandatory operation. Also, here (not in open) is where we should be committing the reboot recovery information. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-05-13nfsd4: nfsd4_destroy_session must set callback client under the state lockBenny Halevy
nfsd4_set_callback_client must be called under the state lock to atomically set or unset the callback client and shutting down the previous one. Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-05-13nfsd4: keep a reference count on client while in useBenny Halevy
Get a refcount on the client on SEQUENCE, Release the refcount and renew the client when all respective compounds completed. Do not expire the client by the laundromat while in use. If the client was expired via another path, free it when the compounds complete and the refcount reaches 0. Note that unhash_client_locked must call list_del_init on cl_lru as it may be called twice for the same client (once from nfs4_laundromat and then from expire_client) Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-05-13nfsd4: mark_client_expiredBenny Halevy
Mark the client as expired under the client_lock so it won't be renewed when an nfsv4.1 session is done, after it was explicitly expired during processing of the compound. Do not renew a client mark as expired (in particular, it is not on the lru list anymore) Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-05-13nfsd4: introduce nfs4_client.cl_refcountBenny Halevy
Currently just initialize the cl_refcount to 1 and decrement in expire_client(), conditionally freeing the client when the refcount reaches 0. To be used later by nfsv4.1 compounds to keep the client from timing out while in use. Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-05-13vfs: Fix O_NOFOLLOW behavior for paths with trailing slashesJan Kara
According to specification mkdir d; ln -s d a; open("a/", O_NOFOLLOW | O_RDONLY) should return success but currently it returns ELOOP. This is a regression caused by path lookup cleanup patch series. Fix the code to ignore O_NOFOLLOW in case the provided path has trailing slashes. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Reported-by: Marius Tolzmann <tolzmann@molgen.mpg.de> Acked-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-12Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: ceph: preserve seq # on requeued messages after transient transport errors ceph: fix cap removal races ceph: zero unused message header, footer fields ceph: fix locking for waking session requests after reconnect ceph: resubmit requests on pg mapping change (not just primary change) ceph: fix open file counting on snapped inodes when mds returns no caps ceph: unregister osd request on failure ceph: don't use writeback_control in writepages completion ceph: unregister bdi before kill_anon_super releases device name
2010-05-12CacheFiles: Fix error handling in cachefiles_determine_cache_security()David Howells
cachefiles_determine_cache_security() is expected to return with a security override in place. However, if set_create_files_as() fails, we fail to do this. In this case, we should just reinstate the security override that was set by the caller. Furthermore, if set_create_files_as() fails, we should dispose of the new credentials we were in the process of creating. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-12Inotify: undefined reference to `anon_inode_getfd'Russell King
Fix: fs/built-in.o: In function `sys_inotify_init1': summary.c:(.text+0x347a4): undefined reference to `anon_inode_getfd' found by kautobuild with arms bcmring_defconfig, which ends up with INOTIFY_USER enabled (through the 'default y') but leaves ANON_INODES unset. However, inotify_user.c uses anon_inode_getfd(). Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Eric Paris <eparis@redhat.com>
2010-05-12Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: Documentation/feature-removal-schedule.txt drivers/net/wireless/ath/ar9170/usb.c drivers/scsi/iscsi_tcp.c net/ipv4/ipmr.c
2010-05-11ceph: preserve seq # on requeued messages after transient transport errorsSage Weil
If the tcp connection drops and we reconnect to reestablish a stateful session (with the mds), we need to resend previously sent (and possibly received) messages with the _same_ seq # so that they can be dropped on the other end if needed. Only assign a new seq once after the message is queued. Signed-off-by: Sage Weil <sage@newdream.net>
2010-05-11ceph: fix cap removal racesSage Weil
The iterate_session_caps helper traverses the session caps list and tries to grab an inode reference. However, the __ceph_remove_cap was clearing the inode backpointer _before_ removing itself from the session list, causing a null pointer dereference. Clear cap->ci under protection of s_cap_lock to avoid the race, and to tightly couple the list and backpointer state. Use a local flag to indicate whether we are releasing the cap, as cap->session may be modified by a racing thread in iterate_session_caps. Signed-off-by: Sage Weil <sage@newdream.net>
2010-05-12[CIFS] drop quota operation stubsSteve French
CIFS has stubs for XFS-style quotas without an actual implementation backing them, hidden behind a config option not visible in Kconfig. Remove these stubs for now as the quota operations will see some major changes and this code simply gets in the way. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jeff Layton <jlayton@samba.org> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-05-11nfsd4: refactor expire_clientBenny Halevy
Separate out unhashing of the client and session. To be used later by the laundromat. Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-05-11nfsd4: extend the client_lock to cover cl_lruBenny Halevy
To be used later on to hold a reference count on the client while in use by a nfsv4.1 compound. Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-05-11nfsd4: use list_move in move_to_confirmedBenny Halevy
rather than list_del_init, list_add Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-05-11nfsd4: fold release_session into expire_clientBenny Halevy
and grab the client lock once for all the client's sessions. Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-05-11nfsd4: rename sessionid_lock to client_lockBenny Halevy
In preparation to share the lock's scope to both client and session hash tables. Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-05-11revert "procfs: provide stack information for threads" and its fixup commitsRobin Holt
Originally, commit d899bf7b ("procfs: provide stack information for threads") attempted to introduce a new feature for showing where the threadstack was located and how many pages are being utilized by the stack. Commit c44972f1 ("procfs: disable per-task stack usage on NOMMU") was applied to fix the NO_MMU case. Commit 89240ba0 ("x86, fs: Fix x86 procfs stack information for threads on 64-bit") was applied to fix a bug in ia32 executables being loaded. Commit 9ebd4eba7 ("procfs: fix /proc/<pid>/stat stack pointer for kernel threads") was applied to fix a bug which had kernel threads printing a userland stack address. Commit 1306d603f ('proc: partially revert "procfs: provide stack information for threads"') was then applied to revert the stack pages being used to solve a significant performance regression. This patch nearly undoes the effect of all these patches. The reason for reverting these is it provides an unusable value in field 28. For x86_64, a fork will result in the task->stack_start value being updated to the current user top of stack and not the stack start address. This unpredictability of the stack_start value makes it worthless. That includes the intended use of showing how much stack space a thread has. Other architectures will get different values. As an example, ia64 gets 0. The do_fork() and copy_process() functions appear to treat the stack_start and stack_size parameters as architecture specific. I only partially reverted c44972f1 ("procfs: disable per-task stack usage on NOMMU") . If I had completely reverted it, I would have had to change mm/Makefile only build pagewalk.o when CONFIG_PROC_PAGE_MONITOR is configured. Since I could not test the builds without significant effort, I decided to not change mm/Makefile. I only partially reverted 89240ba0 ("x86, fs: Fix x86 procfs stack information for threads on 64-bit") . I left the KSTK_ESP() change in place as that seemed worthwhile. Signed-off-by: Robin Holt <holt@sgi.com> Cc: Stefani Seibold <stefani@seibold.net> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Ingo Molnar <mingo@elte.hu> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-11ceph: zero unused message header, footer fieldsSage Weil
We shouldn't leak any prior memory contents to other parties. And random data, particularly in the 'version' field, can cause problems down the line. Signed-off-by: Sage Weil <sage@newdream.net>
2010-05-11cifs: guard against hardlinking directoriesJeff Layton
When we made serverino the default, we trusted that the field sent by the server in the "uniqueid" field was actually unique. It turns out that it isn't reliably so. Samba, in particular, will just put the st_ino in the uniqueid field when unix extensions are enabled. When a share spans multiple filesystems, it's quite possible that there will be collisions. This is a server bug, but when the inodes in question are a directory (as is often the case) and there is a collision with the root inode of the mount, the result is a kernel panic on umount. Fix this by checking explicitly for directory inodes with the same uniqueid. If that is the case, then we can assume that using server inode numbers will be a problem and that they should be disabled. Fixes Samba bugzilla 7407 Signed-off-by: Jeff Layton <jlayton@redhat.com> CC: Stable <stable@kernel.org> Reviewed-and-Tested-by: Suresh Jayaraman <sjayaraman@suse.de> Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-05-11CacheFiles: Fix occasional EIO on call to vfs_unlink()David Howells
Fix an occasional EIO returned by a call to vfs_unlink(): [ 4868.465413] CacheFiles: I/O Error: Unlink failed [ 4868.465444] FS-Cache: Cache cachefiles stopped due to I/O error [ 4947.320011] CacheFiles: File cache on md3 unregistering [ 4947.320041] FS-Cache: Withdrawing cache "mycache" [ 5127.348683] FS-Cache: Cache "mycache" added (type cachefiles) [ 5127.348716] CacheFiles: File cache on md3 registered [ 7076.871081] CacheFiles: I/O Error: Unlink failed [ 7076.871130] FS-Cache: Cache cachefiles stopped due to I/O error [ 7116.780891] CacheFiles: File cache on md3 unregistering [ 7116.780937] FS-Cache: Withdrawing cache "mycache" [ 7296.813394] FS-Cache: Cache "mycache" added (type cachefiles) [ 7296.813432] CacheFiles: File cache on md3 registered What happens is this: (1) A cached NFS file is seen to have become out of date, so NFS retires the object and immediately acquires a new object with the same key. (2) Retirement of the old object is done asynchronously - so the lookup/create to generate the new object may be done first. This can be a problem as the old object and the new object must exist at the same point in the backing filesystem (i.e. they must have the same pathname). (3) The lookup for the new object sees that a backing file already exists, checks to see whether it is valid and sees that it isn't. It then deletes that file and creates a new one on disk. (4) The retirement phase for the old file is then performed. It tries to delete the dentry it has, but ext4_unlink() returns -EIO because the inode attached to that dentry no longer matches the inode number associated with the filename in the parent directory. The trace below shows this quite well. [md5sum] ==> __fscache_relinquish_cookie(ffff88002d12fb58{NFS.fh,ffff88002ce62100},1) [md5sum] ==> __fscache_acquire_cookie({NFS.server},{NFS.fh},ffff88002ce62100) NFS has retired the old cookie and asked for a new one. [kslowd] ==> fscache_object_state_machine({OBJ52,OBJECT_ACTIVE,24}) [kslowd] <== fscache_object_state_machine() [->OBJECT_DYING] [kslowd] ==> fscache_object_state_machine({OBJ53,OBJECT_INIT,0}) [kslowd] <== fscache_object_state_machine() [->OBJECT_LOOKING_UP] [kslowd] ==> fscache_object_state_machine({OBJ52,OBJECT_DYING,24}) [kslowd] <== fscache_object_state_machine() [->OBJECT_RECYCLING] The old object (OBJ52) is going through the terminal states to get rid of it, whilst the new object - (OBJ53) - is coming into being. [kslowd] ==> fscache_object_state_machine({OBJ53,OBJECT_LOOKING_UP,0}) [kslowd] ==> cachefiles_walk_to_object({ffff88003029d8b8},OBJ53,@68,) [kslowd] lookup '@68' [kslowd] next -> ffff88002ce41bd0 positive [kslowd] advance [kslowd] lookup 'Es0g00og0_Nd_XCYe3BOzvXrsBLMlN6aw16M1htaA' [kslowd] next -> ffff8800369faac8 positive The new object has looked up the subdir in which the file would be in (getting dentry ffff88002ce41bd0) and then looked up the file itself (getting dentry ffff8800369faac8). [kslowd] validate 'Es0g00og0_Nd_XCYe3BOzvXrsBLMlN6aw16M1htaA' [kslowd] ==> cachefiles_bury_object(,'@68','Es0g00og0_Nd_XCYe3BOzvXrsBLMlN6aw16M1htaA') [kslowd] remove ffff8800369faac8 from ffff88002ce41bd0 [kslowd] unlink stale object [kslowd] <== cachefiles_bury_object() = 0 It then checks the file's xattrs to see if it's valid. NFS says that the auxiliary data indicate the file is out of date (obvious to us - that's why NFS ditched the old version and got a new one). CacheFiles then deletes the old file (dentry ffff8800369faac8). [kslowd] redo lookup [kslowd] lookup 'Es0g00og0_Nd_XCYe3BOzvXrsBLMlN6aw16M1htaA' [kslowd] next -> ffff88002cd94288 negative [kslowd] create -> ffff88002cd94288{ffff88002cdaf238{ino=148247}} CacheFiles then redoes the lookup and gets a negative result in a new dentry (ffff88002cd94288) which it then creates a file for. [kslowd] ==> cachefiles_mark_object_active(,OBJ53) [kslowd] <== cachefiles_mark_object_active() = 0 [kslowd] === OBTAINED_OBJECT === [kslowd] <== cachefiles_walk_to_object() = 0 [148247] [kslowd] <== fscache_object_state_machine() [->OBJECT_AVAILABLE] The new object is then marked active and the state machine moves to the available state - at which point NFS can start filling the object. [kslowd] ==> fscache_object_state_machine({OBJ52,OBJECT_RECYCLING,20}) [kslowd] ==> fscache_release_object() [kslowd] ==> cachefiles_drop_object({OBJ52,2}) [kslowd] ==> cachefiles_delete_object(,OBJ52{ffff8800369faac8}) The old object, meanwhile, goes on with being retired. If allocation occurs first, cachefiles_delete_object() has to wait for dir->d_inode->i_mutex to become available before it can continue. [kslowd] ==> cachefiles_bury_object(,'@68','Es0g00og0_Nd_XCYe3BOzvXrsBLMlN6aw16M1htaA') [kslowd] remove ffff8800369faac8 from ffff88002ce41bd0 [kslowd] unlink stale object EXT4-fs warning (device sda6): ext4_unlink: Inode number mismatch in unlink (148247!=148193) CacheFiles: I/O Error: Unlink failed FS-Cache: Cache cachefiles stopped due to I/O error CacheFiles then tries to delete the file for the old object, but the dentry it has (ffff8800369faac8) no longer points to a valid inode for that directory entry, and so ext4_unlink() returns -EIO when de->inode does not match i_ino. [kslowd] <== cachefiles_bury_object() = -5 [kslowd] <== cachefiles_delete_object() = -5 [kslowd] <== fscache_object_state_machine() [->OBJECT_DEAD] [kslowd] ==> fscache_object_state_machine({OBJ53,OBJECT_AVAILABLE,0}) [kslowd] <== fscache_object_state_machine() [->OBJECT_ACTIVE] (Note that the above trace includes extra information beyond that produced by the upstream code). The fix is to note when an object that is being retired has had its object deleted preemptively by a replacement object that is being created, and to skip the second removal attempt in such a case. Reported-by: Greg M <gregm@servu.net.au> Reported-by: Mark Moseley <moseleymark@gmail.com> Reported-by: Romain DEGEZ <romain.degez@smartjog.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-11ceph: fix locking for waking session requests after reconnectSage Weil
The session->s_waiting list is protected by mdsc->mutex, not s_mutex. This was causing (rare) s_waiting list corruption. Fix errors paths too, while we're here. A more thorough cleanup of this function is coming soon. Signed-off-by: Sage Weil <sage@newdream.net>
2010-05-11ceph: resubmit requests on pg mapping change (not just primary change)Sage Weil
OSD requests need to be resubmitted on any pg mapping change, not just when the pg primary changes. Resending only when the primary changes results in occasional 'hung' requests during osd cluster recovery or rebalancing. Signed-off-by: Sage Weil <sage@newdream.net>
2010-05-11ceph: fix open file counting on snapped inodes when mds returns no capsSage Weil
It's possible the MDS will not issue caps on a snapped inode, in which case an open request may not __ceph_get_fmode(), botching the open file counting. (This is actually a server bug, but the client shouldn't BUG out in this case.) Signed-off-by: Sage Weil <sage@newdream.net>